Integration Modules

Integration modules are main software modules which run numerical time integration schemes or serve as the main solver in static problem. Thus, an integration module is used to model the majority of the structural system. In the network communication, the integration modules act as a clients while substructure modules act as servers. Depending on the nature of the problems, one of several integration modules can be used for multi-platform or hybrid simulations.

UI-SimCor v3.0

UI-SimCor has been developed in NEES at the UIUC facility to facilitate geographically distributed pseudo-dynamic hybrid simulations. It has been widely used for PSD hybrid simulations and for multi-platform simulations. Due to the open source code and transparent architecture of the code, it has been also used to implement and verify new integration algorithms by researchers. A stable version (v2.8) can be downloaded from the NEEShub. A new version (v3.0) which is compatible with the UTNP communication protocol and all substructure modules introduced on this website will be available for download soon

Cyrus

Cyrus is a main integration program for VecTor program suite that has been developed by Professors Kwon and Vecchio. VecTor programs are nonlinear finite element analysis program developed by Professor Vecchio at the University of Toronto for the analysis of reinforced concrete (RC) structures. The program utilizes a smeared, macro-modeling approach based on the Disturbed Stress Field Model which is derived from the Modified Compression Field Theory. The latter is a widely recognized model for reinforced concrete forming the basis of many analysis models and design specifications world-wide, including the CSA A23.3-05 provisions for design of reinforced concrete members in shear. Each VecTor program has different analysis capabilities as below.

The integration module, Cyrus, can integrate numerical models in VecTor2, 3, 4, and 5. While Cyrus has been developed mainly for the integration of VecTor programs, it also allow integration of any other substructure modules that are within the UT-SIM framework.

With the increasing interests in the performance-based design, S-FRAME has partnered with the University of Toronto to integrated the VecTor program suit with the analysis-design software. In the near future, a structural engineer will be able to design a complicated concrete structure using the current approach (i.e. linear elastic analysis and design following the design code). Then, critical concrete elements such as link beams or shear walls will be able to replaced with refined models in the VecTor suite of programs which will allow for the assessment of the actual performance of the structure. Because the integration is based on the standard communication protocol and data exchange format (UTNP), S-Frame will be able to integrate with any other substructure modules within the UT-SIM framework.

OpenSees

OpenSees is one of the most widely used open-source analysis software in the field of earthquake engineering. The program includes a large number of hysteretic models which can be used to simulate the complex cyclic behaviour of structural elements. The software also includes state-of-art soil material models which can simulate the behaviour of cohesionless soils and liquefaction effect as well as cohesive soils.

To allow for the use of OpenSees as an integration module in the UT-SIM framework, the UTNP communication protocol was imlmented in a generic substructure element of OpenSees. In addition, OpenSeesSP and OpenSeesMP were compiled in the General Purpose Cluster (GPC) in SciNet. A script was developed to tunnel communication from a desktop computer through a login node to the computing node where OpenSeesSP or OpenSeesMP runs such that a large model of soil domain can be simulated with OpenSeesSP in the supercomputer while a detailed structural model can be simulated on a personal desktop computer (or even modelled as a physical specimens).

Custom integration modules

The above integration modules are four examples of potential integration modules. As a matter of fact, all real-time hybrid or multi-platform simulations are, in a sense, substructure analyses. As long as any analysis program can communicate with other programs to exchange data of predicted displacements and velocities, and calculated (or measured) restoring forces, the program can serve as an integration module. Any institution or group that is interested in using their own program as a main integration module and use it to integrate any of the substructure modules, including physical specimens, they can contact the UT-SIM team for technical support and further research collaboration.